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Brosky
01-01-2008, 04:40 PM
Ever wonder what's really inside that switch that doesn't seem to do anything for your lights in the center of your TR6 dash? Well, here you are in living color.

The first post is the disassembly and the next will be cleaned and back together.

I had to grind off the hold down tabs and then the back just pops off. There was a good bit of crud on the contacts as well as the front and rear plates. Some contact cleaner and Never Dull took care of the tarnished copper and silver.

Brosky
01-01-2008, 04:44 PM
The first three show the crud on the inside and # 4 is everything all cleaned before assembly. Here it is cleaned up and glued back together with JB Weld. I did clean up the housing as well, but no pics until the weld is dry tomorrow.

This is the first stage of getting ready to pull the dash in the spring and install my new wood, along with cleaned gauges that I can hopefully make a little brighter by doing this and adding the 8 watt bulbs.

01-01-2008, 04:51 PM
Looks like Egyptian tomb art inside that thing. Glad you did it, I just bypassed mine. A lot easier.

Bugeye58
01-01-2008, 04:53 PM
Paul, aren't you worried about the heat generated by the 8W bulbs?
Jeff

tomshobby
01-01-2008, 05:25 PM
Good job Paul, and I suspect that pics of a certain beautiful new dash will be soon to follow?

Brosky
01-01-2008, 05:26 PM
Jeff,

I talked to a guy at the Cape Cod Fall Show last year and he ran them all summer in his TR6 with no problems. I have some spare gauges that I'm going to clean up and test. I will install the bulbs in those and hook them to my 12V power supply and let them on for a few hours to see just how hot they get on the bench before putting everything back together.

Bill, I was thinking the same thing. More along the lines of the space ship that landed in the last year of the X-Files.

Brosky
01-01-2008, 06:51 PM
Oh yes, Tom. Here it is, awaiting gauges and warm weather.

bcbennett
01-01-2008, 07:42 PM
Paul, thank you for these photos. My rheostat is toast, and you've inspired me to try to repair it. What weird innards!

poolboy
01-01-2008, 07:46 PM
Beautiful piece of wood. Something like that on a gun stock would be big bucks. Is that solid wood or veneer?

NutmegCT
01-01-2008, 08:08 PM
Paul - that dash panel is fantastic. Beautiful wood and beautiful finish.

Bravo!
Tom

Brosky
01-01-2008, 08:13 PM
Thanks guys,

It's a veneer and the pictures don't do it justice. You can see the grain and colors clearly from 10 feet a way. I got very lucky on ebay and as it turned out, the guy who made this one timer is here in MA, only about 40 miles away.

His main business is Jag & Healey dashes and wood and he did this and a TR4 dash as an experiment to see if he would want to mass produce them.

https://www.austinhealeywood.com/wood.html

swift6
01-01-2008, 08:16 PM
the guy who made this one timer is here in MA, only about 40 miles away.

His main business is Jag & Healey dashes and wood and he did this and a TR4 dash as an experiment to see if he would want to mass produce them.

So if that is a 'one-timer', was his answer 'no' for mass producing Triumph dashes?

Brosky
01-01-2008, 08:23 PM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] My rheostat is toast, and you've inspired me to try to repair it.[/QUOTE]

BC,

You will probably find a corrosion build up across the plates that won't allow current to flow. Be careful with the contacts. They're not dainty, but are copper, nonetheless.

This was a $10 ebay switch that I bought so I could learn how to rebuild it, rather than make a mistake with mine.

I may add power to it and test it with the 8 watt bulbs to see how hot it gets as well. I will need to find some sockets to fit the gauges to do so. Rheostats do build up heat and that is their biggest enemy.

Oh well, back to ebay to scrounge up a dash harness for parts.

Hey Dale, do you have any lamp sockets left from your harness swap? I can return them after the testing of the bilbs.

Brosky
01-01-2008, 08:27 PM
Shawn,

He said he was interested in making more as soon as he completes a big order from his main Jag customer for many wooden dash parts.

I think that the TR4 dash was the same gloss, but in black walnut.

I may ask him if I could visit him and take some pictures of his operation. Maybe I could get a field day for the Cape Cod Club organized if he's willing to show his place off. Some guys aren't willing to do that and some are.

jjbunn
01-01-2008, 09:36 PM
I'd always assumed that rheostat was a wirewound device. I wonder why they used an etched board?

DNK
01-01-2008, 10:10 PM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
Hey Dale, do you have any lamp sockets left from your harness swap? I can return them after the testing of the bilbs.
Paul, if Dale doesn't come thru I still have 90% of my old wiring.

2wrench
01-01-2008, 10:33 PM
Beautiful work, as usual, Paul. And that dash is
very pretty, too.

TR3driver
01-02-2008, 12:06 AM
Earlier cars (like the TR3A) were wire-wound.

But to get what appears to be a linear dimming effect, the resistance needs to be logarithmic. Not sure, but I'd guess that's why they went to the thick film thing. If you follow the trace, it gets much longer and thinner as you go around the dial; meaning a larger change in resistance between each pair of pads.

70herald
01-02-2008, 12:56 AM
A wire wound rheostat can be wound in either linear or logarithmic fashion, to make them linear, they just need a variable density, or more likely then core used to wind the resistance wire on varies in diameter. In the old days when audio components were all linear inside, good quality audio equipment used wire wound rheostats, and audio for similar reasons (response) normally use logarithmic rheostats.
Most likely they went to an etched PCB type to reduce costs. Good wire wound rheostats are expensive to manufacture. PCB type stats are cheap.

01-02-2008, 02:33 AM
Thoroughly Modern Millie. Lot smaller in size. Unlike the heater rheostat which has to pull more amps.

Brosky
01-02-2008, 08:32 AM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Paul, if Dale doesn't come thru I still have 90% of my old wiring. [/QUOTE]

Don,

Thanks for the offer. Does the new Masters harness include new sockets? Maybe I can buy a set from him rather than cutting up a good used harness. If you don't care about them, I would certainly take them or pay you for them. Let me know via PM.

70herald
01-02-2008, 09:44 AM
Unlike the heater rheostat which has to pull more amps.
Um unless there are a different number of lamps (or really total wattage) and the lighting range is the same, the rheostat is going to have to control the same voltage / amperage load, and to reduce the lighting the same amount will have to dissipate the same amount of heat. So the amperage will be the same. Still much cheaper to manufacture.

Brosky
01-02-2008, 10:45 AM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Um unless there are a different number of lamps (or really total wattage) [/QUOTE]

The conversation that you have going is different than my comment, but you have a good point and this is why I wanted to bench test a full set of gauges with the switch to see if the 8 watt bulbs would be a problem.

TR3driver
01-02-2008, 03:03 PM
A wire wound rheostat can be wound in either linear or logarithmic fashion, Do you perhaps have an example of a wire-wound logarithmic rheostat ? I'd like to see one ... in spite of hanging about near the lunatic fringe of audiophile-dom, I've never seen or heard of such a thing. Digikey doesn't even bother specifying taper for wire-wounds, as they are all linear. Honeywell doesn't make them either.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]In the old days when audio components were all linear inside, good quality audio equipment used wire wound rheostats,[/QUOTE]I beg to differ. Wire-wound pots are noisy compared to good carbon composition, so they are(were) used only in places where power dissipation was important (like speaker crossover networks) and noise less so (ditto). In fact, the ultimate volume control was always a multi-position switch with discrete resistors between the contacts, similar in theory to the PC-board dimmer, because the contacts could be made with low-noise alloys and not carbon.

I have a very modest collection of antique high fidelity equipment, including an HH Scott tuner and Marantz amplifier (the Dynaco's power transformer bit the dust while I was in college and I stupidly didn't save the remains); and the only wire-wound pots are in the filament balancing circuit and the speaker cross-overs.

Brosky
01-02-2008, 08:19 PM
Before and after. All back together and waiting for sockets to test the switch and 8 watt bulbs.

2wrench
01-02-2008, 08:53 PM
Looks brand new, Paul.

Brosky
01-02-2008, 08:56 PM
2W,

Just a little elbow grease, contact cleaner and Never Dull. It has to work better after removing the crap off of the etched faces and all of the crud from the contacts.

DNK
01-02-2008, 10:49 PM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Paul, if Dale doesn't come thru I still have 90% of my old wiring.

Don,

Thanks for the offer. Does the new Masters harness include new sockets? Maybe I can buy a set from him rather than cutting up a good used harness. If you don't care about them, I would certainly take them or pay you for them. Let me know via PM. [/QUOTE]
After reading your post it just hit me what you asked for. Sorry to lead you on but the gauge sockets don't come with the kit and you use the old. I remember Dale got new tail light sockets I think,maybe he got dash ones too.
Sorry Paul /bcforum/images/%%GRAEMLIN_URL%%/wall.gif

Tinster
01-03-2008, 05:11 AM
Hey Paul,

The Dan Masters Power Block uses the existing light
sockets. I had to replace a few tail light sockets and
bought them at Western Auto. Dan's wires are of much
higher quality than the Triumph OEM.

The dash light sockets and light bulbs for which you are
looking may be purchased at British Wiring in Philadelphia.
Also they have the upgraded wires. Nice folks there, very
helpful. Give them a holler.

https://www.britishwiring.com/CAT00_35.PDF

d

Brosky
01-03-2008, 06:16 PM
Thanks Dale & Don. I'll call them tomorrow.